Related Experiment Video
Updated: Aug 15, 2026

NADH Fluorescence Imaging of Isolated Biventricular Working Rabbit Hearts
Published on: July 24, 2012
Diurnal variation in plasma norepinephrine in patients with heart failure
B E Bleske1, H S Chung, M DiMagno
1University of Michigan College of Pharmacy, Ann Arbor 48109-1065, USA.
Abstract:
Diurnal variation in plasma norepinephrine (PNE) levels is well documented in healthy individuals but not in patients with heart failure. Therefore, we attempted to determine variations in PNE levels over 24 hours, measured hourly, in six patients with an ejection fraction below 40% and a history of heart failure of longer than 3 months. Three controls without a history of heart failure also were evaluated. Both patients and controls had diurnal variations in PNE, with highest levels occurring during the day and lowest at night. When data in patients were evaluated by 6-hour time intervals the mean value for 6:00 A.M.-12:00 noon was approximately twice as high as 12:00 midnight-6:00 A.M. (689+/-329 vs 338+/-166 pg/ml, p<0.05, respectively). Patients also had significant peak to trough variation in PNE levels compared with controls (959+/-396 vs 386+/-84 pg/ml, p<0.02, respectively). These results suggest that significant intrapatient variations in PNE occur over 24 hours in patients with heart failure. These variations may have to be accounted for when evaluating and treating patients with heart failure.
More Related Videos
04:20Integration of Brain Tissue Saturation Monitoring in Cardiopulmonary Exercise Testing in Patients with Heart Failure
Published on: October 1, 2019
07:49A Pacing-Controlled Procedure for the Assessment of Heart Rate-Dependent Diastolic Functions in Murine Heart Failure Models
Published on: July 21, 2023
Related Concept Videos
Heart Failure Drugs: β-Blockers
Chronopharmacokinetics: Circadian Rhythms and Influence on Drug Response
The time of drug administration is an important factor to consider, as it can influence the toxic dose of a drug. For example, a study conducted by Prins et al. in 1997 examined the effects of the timing of...
Heart Failure II: Pathophysiology
Heart Failure III: Clinical Manifestations
Heart Failure VI: Adjunct Therapies
Heart Failure VII: Nursing Interventions